The effect of O ion implantation upon the properties of Sn-doped thin films, which had been sputter-deposited onto glass substrates from a planar magnetron source, was studied. The films were characterized as a function of the implanted dose (3 x 1013 to 1016/cm2) by using Hall effect, resistivity and optical transmission techniques. The results were explained in terms of the deactivation of the Sn dopant, and the removal of O vacancies. An estimate could therefore be made of the amount of electrically active Sn which contributed to the carrier density in as-deposited films. Associated changes in the band gap, with decreasing free-carrier density, could be explained quantitatively in terms of the Burstein-Moss effect.

T.J.Vink, M.H.F.Overwijk, W.Walrave: Journal of Applied Physics, 1996, 80[7], 3734-8